The story of the incredibly famed, Panerai ref. 3646 begins with one particular species of the watch that the world knows better as the Type A ref. 3646. Now, because this is the earliest known of Panerai’s watches — a watch created in war time no less— the Type A’s story begins with a fair amount of ambiguity as to exactly when the watch came into existence. Some will argue that the watch was only designed in 1936, produced in 1937 and delivered in 1938. In any case, it is safe to assume that it was produced sometime after 1935.

For Panerai, the assigned task from the Italian Navy, known as the Regia Marina then, was to produce a watch that could be taken underwater and there, remain legible. Panerai, rather than going through the trouble of trying to figure out how to make a watchcase that could keep water out, went to Rolex SA, who already had a waterproof case patented, which was the Oyster case.

So you see these first of the ref. 3646 watches produced, the Type A, are very special, because these are the ones that went into war and witnessed war. It is, therefore, that we know the Type A also as the “Warbirds”.

Panerai obtained the case and movement for these watches directly from Rolex. These would have sported the California dial, made to Panerai’s specifications with a radium paste applied in between the dial layers so as to make it visible in the dark (obviously, it was glowing because radium is radioactive).

Quite the interesting turn of events though, wouldn’t you say? Because Rolex (a British company) was supplying parts to Panerai via an agent in Venice, who were making watches for the Italian Navy fighting the World War on the other side of the fence. But that’s another story altogether.

The earliest of the Type As came fitted with the Oyster crown, which came with the supplied Rolex movement, but that would soon be replaced with the onion one. What you have to remember here is that all of this was happening in a time when no one had thought of doing warfare underwater in such a manner before.

So the first of these combat divers were suited up in what can only be politely described as the advent of dive suits: a lanolin-soaked wool suit that was topped off with a layer of rubber provided by Pirelli. It wasn’t the most dexterous of solutions, so to have to use the Oyster crown with such a cumbersome suit often proved disastrous.

There were several problems that were identified within these early ref. 3646s. The first problem was the welded-on wire lugs, which had a high tendency to break off. The second concerned the aforementioned crown and the third related to the movement itself. This movement was the cal. 618 that Rolex exclusively supplied to Panerai at that time, with hour and minute indications only. Imagine having to coordinate a dive mission in war conditions without watches synced to the exact second.

The next problem that was identified was the power reserve. If you were lucky, a well-serviced cal. 618 could push out about 40 hours of juice. Otherwise, the divers found themselves having to wind the watch at every given opportunity to make sure it didn’t die on them halfway through a mission.

This then leads us to the last problem associated with the ref. 3646 case: flooding. The more technical term here is water ingress. This was a fault that arose from the constant usage of the screw-down crown. These crowns didn’t have rubber gaskets then — what they had was a thin lead gasket. If water got in as a result of an incompletely screwed-in crown, a cross-threaded one or one with a damaged gasket, the outcome was positively fatal.

But this has to be said, problems and idiosyncrasies aside — both the historical and the technical — take the few elements described of the Type A above and you essentially have the horological beginnings of Panerai and their iconic Radiomir case. In honor of this very first Panerai watch — the one that started it all — this year, just ahead of SIHH 2017, Panerai has just announced two special edition timepieces, the Radiomir 3 Days Acciaio – 47mm PAM00685 and PAM00687 .

Interesting to note that there are two versions of, somewhat, the same watch that form part of the announcement. Both with the Panerai P.3000 manual winding calibre contained within their 47mm steel Radiomir case. Wire lugs and all, the watches tell the story of the earliest incarnation of the Type A. Then, with inclusion of the onion crown and the 3,6,9,12 dial, what Panerai has given us is the story of the Type A in motion.

Now, turn your attention to the PAM00687 and its “tropical” dial. What we must be careful of is using exactly that word — tropical. In the vintage watch circles, we are used to referring to the dials of watches that have turned a creamy shade of brown over long periods of sun exposure — and we’re talking decades — as “tropical”.

The dial on a true 1930s Type A ref. 3646 would, however, have turned brown long before decades worth of sun exposure because of the word you see on the PAM00687’s face: Radiomir. It was the radioactive radium paste that was used to create the luminescent Type A dials that would’ve caused the dial to brown — far sooner. Ah, what a throwback then the PAM00687 makes.

For curiosity’s sake, there are a few known instances of these earliest ref. 3646s, which because the top layer of their dial surfaces had warped due to the radioactive radium, would’ve had to have been jerry–rigged back into some sense of serviceability by riveting the warped dial back into place. But again, that’s another story for another time.